Papers by Giovanna Preziuso
Per valutare la possibilità di allevare la razza bovina Piemontese in Toscana, sono state prese i... more Per valutare la possibilità di allevare la razza bovina Piemontese in Toscana, sono state prese in considerazione le carcasse e la carne di 6 vitelloni maschi di tale di razza, macellati ad un età media di 14 mesi. Le carcasse sono state valutate per conformazio- ne e stato di ingrassamento e, su di esse, sono state rilevate alcune misure lineari;
The effect of stocking density (16 rabbits/m 2 , 5 rabbits/m 2 , 2.5 rabbits/m 2 , n = 60, Experi... more The effect of stocking density (16 rabbits/m 2 , 5 rabbits/m 2 , 2.5 rabbits/m 2 , n = 60, Experiment 1) and group size (4 rabbits/cage, 8 rabbits/cage, 16 rabbits/cage, n = 88, Experiment 2) on productive performance, carcass and meat quality of a slow-growing rabbit population reared outdoors was investigated in two experiments. The highest stocking density induced the highest skin percentage. Lower stocking densities showed lower lightness of Biceps femoris and higher redness of Longissimus lumborum muscles. Four rabbits/cage group (Experiment 2) showed the highest daily weight gain and slaughter weight and the lowest skin percentage. The muscles of 16 rabbits/cage showed significantly higher pHu than 8 and 4 rabbits/cage. BF of 16 and 4 rabbits/cage showed higher L* value. Productive performance and meat quality of rabbits reared outdoors improved in low group size while stocking density needs more experiments. The best combination of density, group size and total available surface that showed the best production and carcass traits was of 5 rabbits/m 2 , 4 rabbits/cage, and 0.8 m 2 .
Meat Science, 2009
The effect of Outdoor or Indoor housing systems on the growth, welfare and carcass and meat quali... more The effect of Outdoor or Indoor housing systems on the growth, welfare and carcass and meat quality of a local rabbit population was investigated. The slaughter age was 103 ± 2 days. Open-field tests showed an effective capacity of the Outdoor group to combat stressors. Compared to Indoor rabbits, Outdoor rabbits showed better growth performance and higher slaughter weight (SW) (2535 vs 2137 g; P < 0.01). Outdoor housing conditions increased the physical activity of rabbits and their hind legs were more developed (36.1% vs 34.9%; P < 0.01). Slaughter yield was lower in Outdoor rabbits (57.8% vs 58.4% SW; P < 0.05) due to the higher skin proportion (17.2% vs 15.6% SW; P < 0.05). Outdoor rabbit meat showed lower L * value (L. lumborum: 55.6 vs 59.2; P < 0.01; B. femoris: 53.0 vs 55.5; P < 0.01) and cooking loss (L. lumborum: 15.9% vs 18.1%; P < 0.05). Outdoor rabbit hind leg meat was characterized by lower water (74.5% vs 75.1%; P < 0.01) and higher protein (22.9% vs 22.6%; P < 0.01) and fat (1.4% vs 1.1%; P < 0.01) contents; lipids were lower in SFA and higher in MUFA. Outdoor rearing seems to be a possible alternative housing system that allays the ethical concerns of modern consumers while also providing good meat quality.
Journal of Food Quality, 2010
The effect of polyvinyl chloride packaging (PP), vacuum packaging (VP) and modified atmosphere pa... more The effect of polyvinyl chloride packaging (PP), vacuum packaging (VP) and modified atmosphere packaging (MAP) (60% O 2 , 30% CO 2 , 10% N 2 ) on some quality parameters and microbiological profile of beef was studied. Longissimus dorsi samples were examined at 7-day intervals during storage at 4C Ϯ 2C, until 21 days. pH of PP beef increased during storage, whereas in VP and MAP beef remained stable. Superficial color darkened for PP samples, remaining stable until 7 and 21 days for VP and MAP samples, respectively; internal color was not significantly influenced by either storage time and packaging methods. Water-holding capacity was not affected by packaging methods, increasing from 7 to 21 days. VP showed lower lipid oxidation than MAP until 21 days and than PP until 14 days. Total mesophilic counts reached the threshold of 107 ufc/g after 7 days in PP and after 14 and 21 days in MAP and VP, respectively.
Italian Journal of Animal Science, 2010
The aim of this research was to test the effect of floor cage in outdoor pen on productive perfor... more The aim of this research was to test the effect of floor cage in outdoor pen on productive performance and carcass characteristics of a rabbit local population characterized by slow growing rate. A sample of 48 rabbits female 57 days old was divided into two groups: Indoor group, housed in colony cages indoor at the density of 14 animals/m 2 and Outdoor group, in wire net floor colony cages in outdoor pen, at the density of 5 animals/m 2 . The animals were fed a commercial feed and ad libitum alfa-alfa hay. Individual live weight and cage feed consumption were checked every week and feed conversion ratio was calculated; at 103 ± 2 days old a sample of 24 animals was slaughtered and carcass traits were recorded. The results showed that the Outdoor group had the highest live weight and the best daily weight gain, together with an higher feed intake. Outdoor group showed the lower mortality, the higher slaughtering weight, the higher reference carcass incidence and hind leg percentage. These favourable results encouraged this kind of rearing system characterized also by lower investment costs.
Italian Journal of Animal Science, 2012
The aim of this study was to evaluate the evolution during refrigerated storage of the main micro... more The aim of this study was to evaluate the evolution during refrigerated storage of the main microbiological and physicochemical parameters of a traditional Italian fresh sausage, salsiccia toscana. The following parameters were analyzed at Days 0, 6 and 9 of storage: total aerobic mesophilic and psychrotrophic counts, Brochothrix thermosphacta, lactic acid bacteria, Pseudomonadaceae, Enterobacteriaceae, Escherichia coli, Micrococcaceae, yeasts and moulds, Salmonella spp., Listeria monocytogenes; pH, Aw, moisture, protein, total lipids, ash, fatty acid composition, Thiobarbituric Acid Reactive Substances, colour measurement. The results revealed a statistically significant increase in the main microbiological parameters between Days 0 and 9 of refrigerated storage, with total bacterial counts exceeding 10 7 CFU/g after nine days and Brochothrix thermosphacta representing the main spoilage microorganism. Among physicochemical parameters, discolouration was noted during the time of storage, with a significantly paler colour on the surface of sausages with casings after nine days of storage. Considering that the initial bacterial counts were higher than 10 5 CFU/g for Brochothrix thermosphacta, Pseudomonadaceae, lactic acid bacteria and Enterobacteriaceae, and that the product is traditionally purchased loose without any packaging, it is fundamental to improve the good manufacturing practices, particularly measures to control processing temperatures.
Italian Journal of Animal Science, 2010
The purpose of this study was to evaluate the antioxidant status of meat from cattle fed diets su... more The purpose of this study was to evaluate the antioxidant status of meat from cattle fed diets supplemented with vitamin E (α-tocopherol acetate) during the finishing period and to evaluate the effect of this treatment on meat shelf-life. Twenty purebred Limousine calves reared in the same farm, were randomly selected, divided into control group (n=10) and treated group (n=10) and fed a total mixed ration: treated group received a supplementation of vitamin E (900 mg/kg of CMF) for a period of 150 days before slaughter. Meat quality was evaluated by the following analyses: pH, water holding capacity (drip loss), colour (L*, a*, b*, C*, H*), chemical forms of myoglobin, substances reactive to thiobarbituric acid (MDA) and enzymatic antioxidant activity (superoxide dismutase, catalase and glutation peroxidase). Dietary vitamin E supplementation had a positive effect on water holding capacity; in the control group a considerable increase in drip loss from the 2 nd to 6 th day of conservation was observed (2.83% vs 7.54%), while in the treated group during the same time period this increase appeared to be much more gradual and occurred to a lesser degree (2.31% vs 4.15%). Moreover, administration of vitamin E led to greater stability of colorimetric coordinates and reduced discoloration of the longissimus dorsi muscle during conservation as indicated by the redness a* (control: 23.85 and 23.87 vs 19.34 at 2h, 2 and 6 days, respectively; treated: 24.88, 23.91 and 24.01 at 2h, 2 days and 6 days, respectively) and in the Chroma* (control: 26.89 and 26.77 vs 21.90 at 2h, 2 days and 6 days, respectively; treated: 27.67, 26.57 and 26.77 at 2h, 2 and 6 days, respectively). Superoxide dismutase activity was significantly greater in the meat from cattle treated with vitamin E compared to that observed in the meat from controls (0.204 vs 0.167). The study showed that vitamin E supplementation in the finishing diets of calves caused only slight modifications in the antioxidant status of the meat; however, it positively influenced several qualitative characteristics which appeared to be more stable over time, thus extending the shelf-life of the meat.
Italian Journal of Animal Science, 2010
The aim of this study was to evaluate several quality characteristics of meat obtained from 20 Li... more The aim of this study was to evaluate several quality characteristics of meat obtained from 20 Limousine calves slaughtered either according to conventional methods (n=10) or by the Islamic ritual slaughtering procedure (n=10). After 7 days of ageing under va�uum, pH, drip loss, colour and oxymyoglobin percentage were measured on longissimus dorsi muscle after 2h, 2 and 6 days of storage to study their evolution. With conventional slaughter pH remained stable until the 6 th day of storage, while with ritual slaughter it increased from the 2 nd to 6 th day of storage. Drip loss increased considerably from the 2 nd to 6 th day of storage in conventional slaughter, while in ritual slaughter the drip loss increase was lower. Meat colour was not influenced by the slaughtering system but only by the different lengths of storage.
Italian Journal of Animal Science, 2010
The heritability of quality traits (chemical composition, colour, tenderness and water-holding ca... more The heritability of quality traits (chemical composition, colour, tenderness and water-holding capacity) of the meat deriving from three muscles (Triceps brachii, Longissimus dorsi and Semitendinosus) was evaluated in 92 young Chianina bulls. The animals were raised on two farms with different feeding programs, and were slaughtered at approximately 19 months of age. Single pair correlations were considered in order to evidence the relationships between the same traits detected in the three muscles and between all the traits of the same muscle. The h 2 values range from 0.00 to 0.24 for the chemical composition, from 0.00 to 0.19 for colour parameters, from 0.03 to 0.31 for those observed after 48 h, and from 0.00 to 0.08 for tenderness and water-holding capacity. The values were not homogeneous for the three muscles. The most heritable trait was yellowness (b*48) in all three muscles, with values of 0.11 in the Longissimus dorsi, 0.23 in the Semitendinosus, and 0.31 in the Triceps brachii. Conversely, tenderness appeared to have a low heritability, as did the parameters relating to the water-holding capacity. Colour traits observed before and after 48 h of storage generally were significantly and positively correlated, indicating that certain colour characteristics are maintained even after 48 h of storage. There was not always a close relationship between the traits of each muscles: significant correlations existed between the Triceps brachii and the Longissimus dorsi muscles, confirming the similar quality traits of their meat, while there were considerable differences between these muscles and the Semitendinosus. RIASSUNTO IL MIGLIORAMENTO GENETICO DELLA QUALITÀ DELLA CARNE DELLA RAZZA CHIANINA: L'EREDITABILITÀ.
Italian Journal of Animal Science, 2010
Abstract (English) The effects of muscle and slaughtering age on some meat quality traits of 48 c... more Abstract (English) The effects of muscle and slaughtering age on some meat quality traits of 48 carcasses of Chianina beef cattle, raised on the same farm and slaughtered at an age ranging between 18 and 21 months, were studied. After the usual commercial ageing ...
Italian Journal of Animal Science, 2010
The extensive outdoor rearing system is considered capable of satisfying high standards of animal... more The extensive outdoor rearing system is considered capable of satisfying high standards of animal welfare: the effects of outdoor rearing system stocking density on meat quality traits of slow growing rabbits were studied. Sixty rabbits reared in outdoor cages were randomly assigned to three stocking densities: 0.06m 2 /rabbit, 0.2m 2 /rabbit and 0.4m 2 / rabbit. At 102±1 days of age, twelve animals per group were slaughtered and pHu, L* a* b* colour and cooking loss were measured on B. femoris and Lumborum muscles. The animals reared at 0.2 and 0.4m 2 /rabbit density showed a lower lightness of B. femoris muscle and a higher a* value than the other group. The higher disposable space induced greater physical activity, probably increasing muscle oxidative metabolism and consequently inducing less pale meat. Outdoor rearing at low rabbit density seems to satisfy the animals' spatial and social needs, improve sanitary conditions, and furnish good meat quality.
Italian Journal of Animal Science, 2012
To evaluate the effect of genotype on carcass traits and meat quality, sixty-four rabbits belongi... more To evaluate the effect of genotype on carcass traits and meat quality, sixty-four rabbits belonging to two genotypes (slow growing local population, LP; commercial hybrids, HY) were used. Rabbits were weaned at 35 days of age and slaughtered when they reached 2500 g of live weight, corresponding to 103 and 87 days of age for LP and HY, respectively. Comparing the slaughter traits of two genotypes, LP provided higher dressing out (59.4 vs 56.2%, P<0.01) and skin percentage (16.0 vs 14.2%, P<0.05), lower incidence of full gastrointestinal tract (18.5 vs 22.3%, P<0.01) and higher incidence of head (9.5 vs 8,9%, P<0.05) and kidneys (0.99 vs 0.86%, P<0.05) than HY. Reference carcasses from LP had greater incidence of perirenal fat (2.04 vs 1.12%; P<0.01), loin (21.5 vs 19.2%; P<0.01) and hind leg (34.4 vs 31.6%; P<0.01) than HY. Hind leg meat-to-bone ratio was significantly higher in HY than LP (4.7 vs 3.8%; P<0.01). The comparison between the variances of slaughter weight, chilled carcass weight, kidneys percentage, reference carcass weight, perirenal fat and hind leg percentage showed the greatest variability in the LP. Meat derived from LP showed lower L*, higher a*, b* and C* colour values than HY (P<0.01). In conclusion, LP showed good slaughter traits and favourable meat quality. The great variability observed in the LP could allow to improve the productive performances, however maintaining animal rusticity.
Meat science, Jan 11, 2015
The objective of this study was to evaluate the effect of Curcuma longa powder and ascorbic acid ... more The objective of this study was to evaluate the effect of Curcuma longa powder and ascorbic acid on some quality traits of rabbit burgers. The burgers (burgers control with no additives; burgers with 3.5g of turmeric powder/100g meat; burgers with 0.1g of ascorbic acid/100g meat) were analyzed at Days 0 and 7 for pH, color, drip loss, cooking loss, fatty acid profile, TBARS, antioxidant capacity (ABTS, DPPH and FRAP) and microbial growth. The addition of turmeric powder modified the meat color, produced an antioxidant capacity similar to ascorbic acid and determined a lower cooking loss than other formulations. Turmeric powder might be considered as a useful natural antioxidant, increasing the quality and extending the shelf life of rabbit burgers.
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Papers by Giovanna Preziuso